Reinforcing Matrix for Spoolable Pipe

ABSTRACT

A spoolable pipe is disclosed, the spoolable pipe having an internal pressure barrier formed about a longitudinal axis, and a reinforcing layer(s) enclosing the internal pressure barrier that includes a solid hydrocarbon matrix. The pipe can also include an energy conductor(s) integrated with and/or located between the internal pressure barrier and/or the reinforcing layer(s).

CROSS-REFERENCE TO RELATED APPLICATIONS

The current application is a continuation of U.S. patent applicationSer. No. 11/689,199, filed Mar. 21, 2007 which claims priority to andthe benefit of U.S. provisional patent application Ser. No. 60/784,258,filed Mar. 21, 2006. Each of the aforementioned patent applications isincorporated herein by reference in its entirety.

BACKGROUND

Steel pipe is commonly used in the oil and gas industry. This type ofpipe may be used in the transport of fluids to or from the well such asoil and gas gathering lines, flow lines, and fluid and gas injectionlines which may be installed on the surface or buried. Steel pipe mayalso be used for downhole applications such as drilling, intervention,or production including drill strings, coiled tubing, production tubing,casing, and velocity and heater strings, and the like. Carbon steels,however, may be susceptible to corrosion by oilfield fluids, such asproduced or injected water, brine, and dissolved acids from CO₂ or H₂S,as well as well work-over fluids such as HCl and HF. Furthermore, steelpipelines, gathering lines or injection lines are usually installedusing short (30-40 foot) sections. This requires additional labor andprovides the possibility for fluid leakage at each fitting. Such laborintensive installation may also lead to lost revenues if production ortransport of the fluids is suspended during the installation.

To resist internal corrosion, steel alloys, non-metallic internalcoatings, or fiberglass-reinforced epoxy pipe may be used, but all maystill have the disadvantage of being sectional products. In addition,the wall of a fiberglass-reinforced epoxy pipe may be fairly damageintolerant and may require careful handling, installation, and/or use ofspecific back-fill materials. Damage or cracks in thefiberglass-reinforced epoxy layer can, in some cases, lead to smallleaks or “weeping” of the pipe under pressure. In some applications,thermoplastic liners may be used as corrosion protection inside steelpipe, but these liners are susceptible to collapse by permeating gasestrapped in the annulus between the liner and the steel pipe if thepressure of the bore is rapidly decreased. Unreinforced thermoplasticpipe, on the other hand, can usually only tolerate relatively lowpressures especially at elevated temperatures and in the presence ofoilfield fluids.

Thermoplastic lined fiberglass pipe designed for relatively moderatepressure, for example, 0 to about 500 PSI service may have thin wallsthat may be damage intolerant or may kink or collapse when spooled atmoderate spooling strains of about 1-10%. High modulus materials such asepoxies may increase the tendency for the thin-walled pipe to kink orcollapse. Materials such as Kevlar may used for reinforcement but may beprohibitively expensive for many applications. Bare fiberglassreinforcement of, for example, a thermoplastic liner may be susceptibleto corrosion by water, especially in the presence of dilute acids,bases, or stress. Abrasion of bare fibers against each other duringmanufacturing, spooling, installation, or operation may cause breakageof glass fibers and reduction of hydrostatic strength. Uneven surfacesof the fibers against a tube liner may cause point loading; gouging ofthe fibers into the liner may increase the tendency to stress crackingof the liners; individual fibers that can move independently may spreadso as to allow the liner to extrude past the fiber reinforcement andrupture. Therefore, there is a need for a low-cost, corrosion resistant,spoolable, reinforced inner-lined pipe for such relatively low pressureapplications that is damage tolerant and will not kink when spooled.

SUMMARY

Disclosed is a spoolable pipe comprising a matrix that includes solidmatrix with a tensile modulus of less than about 100,000 psi.

For example, a spoolable pipe is disclosed that includes an internalpressure barrier formed about a longitudinal axis; at least onereinforcing layer enclosing the internal pressure barrier and comprisingfibers and a solid hydrocarbon matrix, where the solid hydrocarbonmatrix is solid at about 25° C., and may also include an external layerenclosing the least one reinforcing layer. The hydrocarbon matrix maycomprise hydrocarbons having a molecular weight of less than about10,000 grams/mole.

In some embodiments, the reinforcing layer includes fibers that compriseglass, an aramid, a carbon, a ceramic, a metal, a mineral, or a polymer,or combinations thereof. A reinforcing layer may comprise at least twoplies of fibers, and in some embodiments, at least two plies of fibersmay have at least a partial helical orientation relative to thelongitudinal axis. Such fibers may be embedded in matrix.

The solid hydrocarbon matrix of a disclosed spoolable tube may compriseup to about 30%, up to about 50%, or even up to about 70% by volume of areinforcing layer and/or may comprise up to about 15% by weight of areinforcing layer. For example, the matrix may comprise between about10% and about 70% by volume. In some embodiments, the solid hydrocarbonmatrix may have a tensile strength of less than about 1000 psi. In otherembodiments, the permeability of a disclosed hydrocarbon matrixincreases with temperature faster than the permeability of an internalpressure barrier or liner increases with temperature.

In some embodiments, the solid hydrocarbon matrix included in thespoolable tube may have a content of at least 10% by weight ofhydrocarbons with a molecular weight of less than about 4,000 grams/moleand/or may have a solid hydrocarbon matrix with a molecular weight ofabout 200 to about 8,000 grams/mole. Contemplated hydrocarbons mayinclude straight-chain alkanes, cycloalkanes, branched alkanes, and/oraliphatic compounds. Hydrocarbons contemplated herein may also includealkenes, alkynes, and aromatic functionalities.

Also disclosed herein is a spoolable pipe that includes an internalpressure barrier formed about a longitudinal axis, at least onereinforcing layer enclosing the internal pressure barrier and comprisingfibers and a solid matrix with a tensile modulus between about 10 and90,000 psi, or about 10 to about 10,000 psi, wherein said reinforcinglayer is formed at least by applying to said fibers a substantiallyliquid matrix composition having a viscosity between about 10 and about5,000 cPs at 25° C., or between about 10 and about 10,000 cPs at 25° C.In some embodiments, the substantially liquid matrix composition iscapable of flowing between the fibers of the reinforcing layer.

The substantially liquid matrix composition may have a viscosity betweenabout 100 and about 1000 cPs. In some embodiments, the substantiallyliquid matrix composition is an emulsion, a suspension, a colloid, aimmiscible fluid blend, or two-phase system, and may further include anemulsifier, tackifier, binder, and/or surfactant. In one embodiment, thesubstantially liquid matrix is an emulsion. In another embodiment, thesubstantially liquid matrix comprises a water-based dispersion, e.g.that includes polymer particles. The substantially liquid matrixcomposition may include at least one of: polyethylene, polyethyleneoligomers, polypropylene, polypropylene oligomers, polyolefins,polyolefin oligomers, paraffin waxes, or a grease.

In some embodiments, the substantially liquid matrix compositioncomprises polymer particles. Such polymer particles may have an averagediameter between about 10 nm and about 10 μm.

The internal pressure barrier or liner of a disclosed spoolable tube maycomprise at least one of: a metal, and/or a polymer such as apolyolefin, a polyethylene, cross-linked polyethylene, polyvinylidenefluoride, polyamide, polypropylene, polybutylene, polybutadiene,polyvinylchloride, polyethylene terphthalate, or polyphenylene sulfideor combinations thereof. The barrier may have distinct separate layersor may include combinations of materials such as an alloy, blend,copolymer or block polymer. The internal pressure barrier may alsoinclude organic or inorganic solids.

In some embodiments, the permeability of a reinforcing layer orhydrocarbon matrix of a disclosed spoolable tube may be higher than thepermeability of an internal pressure barrier and/or the permeability ofan external layer may be higher than the permeability of the hydrocarbonmatrix or a reinforcing layer. In some embodiments, the permeability ofan external layer may be less than the permeability of the reinforcinglayer or hydrocarbon matrix.

A disclosed spoolable pipe may include an external layer that comprises,for example, at least one of: polyethylene, cross-linked polyethylene,polyvinylidene fluoride, polyamide, polybutylene, polypropylene,polyethylene terphthalate, or polyphenylene sulfide, or a combinationthereof, either as distinctly separate layers or as alloys, blends,copolymers, or block copolymers. An exemplary external layer includes afoam that comprises for example, at least one of: a thermoset polymer, athermoplastic polymer, elastomer, rubber, a closed cell foam, and anopen cell foam. The external layer may include organic or inorganicsolids. In some embodiments, such an external layer is perforated.Disclosed spoolable pipes may further comprise an energy conductor. Inother embodiments, a spoolable pipe disclosed herein may include a fireretardant UV stabilizer, oxidative stabilizer, thermal stabilizer,and/or a pigment.

The disclosed reinforcing material may include fibers which are at leastpartially coated by said solid hydrocarbon matrix and/or fibers that maybe embedded in said solid hydrocarbon matrix.

Also provided herein is a method for producing a spoolable tubecomprising: providing an inner layer of said spoolable tube; applying asubstantially liquid matrix composition comprising at least one of:polyethylene, polyethylene oligomers, polypropylene, polypropyleneoligomers, polyolefins, polyolefin oligomers, a wax, and/or a grease tofibers at a temperature between about 20° C. and about 40° C.; drying orcuring said fibers so that a solid matrix composition between the fibersis formed; and winding said tow around said inner layer. Thesubstantially liquid matrix composition may be applied at about 25° C.The applying step may occur substantially during the winding step. Insome embodiments, the drying step may occur after, during, or before thewinding step.

In another embodiment, a method for producing a spoolable tube isprovided that comprises: providing an inner layer of the spoolable tube;applying a hydrocarbon matrix comprising hydrocarbons having an averagemolecular weight of less than about 20,000 grams/mole to fibers bydissolving the hydrocarbons in a solvent; cooling or evaporating thesolvent from said fibers so that a solid hydrocarbon matrix is formed onor around the fibers; and winding said fibers around said inner layer.The hydrocarbon matrix may be applied at about 25° C.

Alternatively, a method for producing a spoolable tube is provide thatcomprises: providing an inner layer of the spoolable tube; melting ahydrocarbon matrix comprising hydrocarbons having an average molecularweight of less than about 20,000 grams/mole; applying the meltedhydrocarbon matrix to fibers; cooling the hydrocarbon matrix so that asolid hydrocarbon matrix is formed on or around the fibers; and windingsaid fibers around said inner layer. In some embodiments, asubstantially solid hydrocarbon matrix composition is a wax. The methodsmay further comprise forming a tow comprising said fibers. Thehydrocarbon matrix composition may be applied at a temperature above itsmelting point, for example at about 40 to about 150° C.

In some embodiments, the solid hydrocarbon matrix is formed bycross-linking or gelling the hydrocarbons. Such gelling or cross-linkingof the hydrocarbon matrix may improve the thermal resistance, chemicalresistance, or mechanical properties of the matrix.

The methods include those wherein an applying step occurs substantiallyin-line with the production of the fibers. The applying step of thedisclosed methods may occur, e.g. substantially during the winding step.The cooling or solvent evaporation step may occur after said windingstep. In some embodiments, disclosed methods may also include forming atow comprising said fibers.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view, partially broken away, of a spoolable tube thatincludes an inner pressure barrier and a reinforcing layer.

FIG. 2 is a cross-sectional view of a spoolable tube having an innerpressure barrier surrounded by multiple reinforcing layers.

FIG. 3 is cross-sectional view of a spoolable tube having an innerpressure barrier surrounded by a reinforcing layer that includes twoplies of fibers with an abrasion layer between the two plies.

FIG. 4 is a side view, partially broken away, of a spoolable tube havingan inner pressure barrier, a reinforcing layer, and an external layer.

FIG. 5 is a side view, partially broken away, of a spoolable tube thatincludes an energy conductor.

FIG. 6 indicates various properties of tows that include various lowmolecular weight hydrocarbons with glass fibers.

FIG. 7 shows the distribution of hydrocarbons in an exemplary solidhydrocarbon matrix.

DETAILED DESCRIPTION

To provide an overall understanding, certain illustrative embodimentswill now be described; however, it will be understood by one of ordinaryskill in the art that the systems and methods described herein can beadapted and modified to provide systems and methods for other suitableapplications and that other additions and modifications can be madewithout departing from the scope of the systems and methods describedherein.

Unless otherwise specified, the illustrated embodiments can beunderstood as providing exemplary features of varying detail of certainembodiments, and therefore, unless otherwise specified, features,components, modules, and/or aspects of the illustrations can beotherwise combined, separated, interchanged, and/or rearranged withoutdeparting from the disclosed systems or methods. Additionally, theshapes and sizes of components are also exemplary and unless otherwisespecified, can be altered without affecting the scope of the disclosedand exemplary systems or methods of the present disclosure.

Disclosed herein is a spoolable tube and methods for making the same,that provides a path for conducting fluids (i.e., liquids and gases)along the length of the spoolable tube. For example, the spoolable tubecan transmit fluids down a well hole for operations upon the interiorsurfaces of the well hole, the spoolable tube can transmit fluids orgases to hydraulic or pneumatic machines operably coupled to thespoolable tube, and/or the spoolable tube can be used to transmitfluids, underwater, underground, or on surface systems from well holesor other equipment to transmission, distribution pipelines or otherequipment. Accordingly, the spoolable tube disclosed herein can providea conduit for powering and controlling hydraulic and/or pneumaticmachines, and/or act as a conduit for fluids, for example gases orliquids. In some embodiments, the spoolable tubes disclosed herein areused for relatively low pressure applications, where the pressure of afluid being transported by a disclosed tube is about 1 to about 1000psi, or about 10 to about 500 psi. Such spoolable tubes comprise areinforcing layer that includes a matrix with a tensile modulus of lessthan 100,000 psi, e.g. a tensile modulus between about 1 and about90,000 psi, between about 10 and 90,000 psi, between about 100 and about10,000 psi.

For convenience, before further description, certain terms employed inthe specification, examples, and appended claims are collected here.These definitions should be read in light of the reminder of thedisclosure and understood as by a person of skill in the art.

The articles “a” and “an” are used herein to refer to one or to morethan one (i.e. to at least one) of the grammatical object of thearticle. By way of example, “an element” means one element or more thanone element.

The term “aliphatic” is an art-recognized term and includes linear,branched, and cyclic alkanes, alkenes, or alkynes. In certainembodiments, aliphatic groups in the present disclosure are linear orbranched and have from 10 to about 100 carbon atoms, 12 to about 50carbons, or even 12 to about 35 carbons.

The term “alkyl” is art-recognized, and includes saturated aliphaticgroups, including straight-chain alkyl groups, branched-chain alkylgroups, cycloalkyl (alicyclic) groups, alkyl substituted cycloalkylgroups, and cycloalkyl substituted alkyl groups. In certain embodiments,a straight chain or branched chain alkyl has about 30 or fewer carbonatoms in its backbone (e.g., C1-C30 for straight chain, C3-C30 forbranched chain), and alternatively, about 20 or fewer. Likewise,cycloalkyls have from about 3 to about 10 carbon atoms in their ringstructure, and alternatively about 5, 6 or 8 carbons in the ringstructure.

Moreover, the term “alkyl” (or “lower alkyl”) includes both“unsubstituted alkyls” and “substituted alkyls”, the latter of whichrefers to alkyl moieties having substituents replacing a hydrogen on oneor more carbons of the hydrocarbon backbone. Such substituents mayinclude, for example, a halogen, a hydroxyl, a carbonyl (such as acarboxyl, an alkoxycarbonyl, a formyl, or an acyl), a thiocarbonyl (suchas a thioester, a thioacetate, or a thioformate), an alkoxyl, aphosphoryl, a phosphonate, a phosphinate, an amino, an amido, anamidine, an imine, a silyl, a cyano, a nitro, an azido, a sulfhydryl, analkylthio, a sulfate, a sulfonate, a sulfamoyl, a sulfonamido, asulfonyl, a heterocyclyl, an aralkyl, metals, metal ions, or an aromaticor heteroaromatic moiety. It will be understood by those skilled in theart that the moieties substituted on the hydrocarbon chain maythemselves be substituted, if appropriate. For instance, thesubstituents of a substituted alkyl may include substituted andunsubstituted forms of amino, azido, imino, amido, phosphoryl (includingphosphonate and phosphinate), sulfonyl (including sulfate, sulfonamido,sulfamoyl and sulfonate), and silyl groups, as well as ethers,alkylthios, carbonyls (including ketones, aldehydes, carboxylates, andesters), —CF₃, —CN and the like. Exemplary substituted alkyls aredescribed below. Cycloalkyls may be further substituted with alkyls,alkenyls, alkoxys, alkylthios, aminoalkyls, carbonyl-substituted alkyls,—CF₃, —CN, and the like.

The term “aralkyl” is art-recognized, and includes alkyl groupssubstituted with an aryl group (e.g., an aromatic or heteroaromaticgroup).

The terms “alkenyl” and “alkynyl” are art-recognized, and includeunsaturated aliphatic groups analogous in length and possiblesubstitution to the alkyls described above, but that contain at leastone double or triple bond respectively.

Unless the number of carbons is otherwise specified, “lower alkyl”refers to an alkyl group, as defined above, but having from one to tencarbons, alternatively from one to about six carbon atoms in itsbackbone structure. Likewise, “lower alkenyl” and “lower alkynyl” havesimilar chain lengths.

The term “hydrocarbon” is art-recognized and refers to all permissiblecompounds having at least one hydrogen and one carbon atom. For example,permissible hydrocarbons include acyclic and cyclic, branched andunbranched, carbocyclic and heterocyclic, aromatic and nonaromaticorganic compounds that may be substituted or unsubstituted, for example,alkyl moieties. In some embodiments, hydrocarbons disclosed herein havea molecular weight less than about 50,000, less than about 30,000, lessthan about 10,000, less than about 5,000, less than about 3,000, or evenless than about 2,000 g/mol.

The term ‘olefin’ refers to unsaturated, aliphatic hydrocarbons. Theunsaturated, aliphatic hydrocarbons may be substituted or unsubstituted.

The term “solid” refers to a substance that is resistant to flow, e.g.substantially solid at room temperature (25° C.).

The term “grease” refers to a composition that is organic or inorganic,substantially water-insoluble, and semi-solid at room temperature.

The term “wax” will be understood to encompass any composition that issubstantially solid at room temperature, and can be used at a lowviscosity or high temperature, and then cooled to room temperatureduring the formation of a product disclosed herein. A wax melts withoutsignificant decomposition at a temperature above about 40° C., forexample, with a melting point of about 40° C. to about 120° C. or about40° C. to about 90° C. Wax may include an organic compound that issubstantially carbon and hydrogen based, but may include elements suchas oxygen, nitrogen silicon and/or cationic and anionic moieties.Exemplary waxes include fossil waxes such as petroleum waxes, e.g.ozokerite, macrocristalline paraffin waxes, microcrystalline paraffinwaxes, montan waxes, plant waxes such as carnauba wax, candelilla waxand the like, waxes that include silicon or silicone, waxes of animalorigin such as beeswax, lanolin and the like, and also semisyntheticwaxes such as amide waxes, e.g., distearylethylenediamine, and alsofully synthetic waxes such as polyolefin waxes, e.g., polyethylene andpolypropylene waxes, Fischer-Tropsch waxes, fluorinated waxes such aspolytetrafluoroethylene and polyethylene-polytetrafluoroethylenecopolymers, and also polyoxidates of Fischer-Tropsch waxes and ofpolyolefin waxes. Waxes include compounds that are esters of long-chainaliphatic alcohols (for example C₁₆ and above) with long-chain fattyacids. Such esters and acids are preferably straight-chain compounds,and may be saturated or unsaturated. Examples of acids which may be usedinclude stearic acid, palmitic acid and oleic acid and mixtures of twoor more thereof. Waxes derived from long-chain aliphatic compounds mayinclude hydrocarbons. In addition to esters of the long-chain acids asdescribed above there may be mentioned salts such as, for example,aluminium stearate.

The term “substituted” is art-recognized and refers to all permissiblesubstituents of organic or inorganic compounds. In a broad aspect, thepermissible substituents include acyclic and cyclic, branched andunbranched, carbocyclic and heterocyclic, aromatic and nonaromaticsubstituents of organic or inorganic compounds. Illustrativesubstituents include, for example, those described herein above. Thepermissible substituents may be one or more and the same or differentfor appropriate organic compounds. For purposes of this disclosure, theheteroatoms such as silicon may have hydrogen substituents, halogensubstituents, and/or any permissible substituents of organic orinorganic compounds described herein which satisfy the valences of theheteroatoms. This disclosure is not intended to be limited in any mannerby the permissible substituents of organic or inorganic compounds.

It will be understood that “substitution” or “substituted with” includesthe implicit proviso that such substitution is in accordance withpermitted valence of the substituted atom and the substituent, and thatthe substitution results in a stable compound, e.g., which does notspontaneously undergo transformation such as by rearrangement,cyclization, elimination, or other reaction.

The definition of each expression, e.g. alkyl, m, n, R, X, etc., when itoccurs more than once in any structure, is intended to be independent ofits definition elsewhere in the same structure unless otherwiseindicated expressly or by the context.

In one aspect, this disclosure provides for a material, such as areinforcing layer in a spoolable pipe, that includes fibers and ahydrocarbon matrix. The hydrocarbon matrix may be solid at roomtemperature, but have a lower viscosity at a higher temperature so thatsuch matrix can be applied in liquid form to, for example, fibers.Alternatively, the matrix may be formed, at least in part, by applying asubstantially liquid matrix composition having a viscosity of betweenabout 10 and about 10,000 cPs at 25° C.

The hydrocarbon matrix may include hydrocarbons such as aliphaticcompounds, e.g straight-chain alkanes, cycloalkanes, or branchedalkanes. In other embodiments, the hydrocarbon matrix may include a wax,such as defined above, or a grease, for example a silicone grease,elastomers, rubbers such as butadiene acrylonitrile (NBR) orhydrogenated nitrile butadiene rubber, tars, asphalts, polymer solutionsor blends, emulsions, gels or combinations of these or otherhydrocarbons disclosed herein.

Exemplary hydrocarbons include those compounds that comprise thestructure

where x may independently for each occurrence be an integer from 0 to 2;R may independently for each occurrence be hydrogen, alkyl, alkenyl,alkynyl, aryl, alkoxy, hydroxyl, halogen, amino, nitro, sulfhydryl,amido, phosphonate, phosphinate, silyl, carboxyl, ether, alkylthio,ester, a metal or metal ion, or the like, and n is an integer from about5 to about 300, about 7 to about 100, about 12 to about 25, or about 15to about 30.

Such hydrocarbons that may be included in a matrix may have a molecularweight or weight average molecular weight of less than about 50,000,less than about 30,000, less than about 20,000, or even less than about10,000 g/mol. For example, a solid hydrocarbon contemplated herein mayhave a molecular weight of about 200 to about 8,000 g/mol, about 400 toabout 12,000 g/mol, or about 250 to about 15,000 g/mol. In someembodiments, a solid hydrocarbon matrix may have between about 10 andabout 2000 repeating monomeric units, e.g. about 10 to about 1500, orabout 100 to about 1500 repeating units. A hydrocarbon matrix may have acontent of at least about 5%, at least about 10%, or even at least about20% by weight of hydrocarbons with a molecular weight of less than forexample 20,000, less than about 10,000 or even less that about 5,000, orless that about 4,000 grams/mol. A solid hydrocarbon matrix or wax mayhave a weight average molecular weight falling within the ranges setforth above. For example, a solid hydrocarbon matrix may include suchwaxes as Microsere 5701.

For example, an elemental analysis of a such a substantially hydrocarbonmatrix may include C_(x)H_(y)A_(z)R_(m)R′_(m)R″_(m)M_(n) where R, R′ andR″ may each independently include a halogen such as F, Cl or I; A is aheteroatom; M is a metal and where x is about 1.0; y may be about1.0-3.0 inclusive; z is about 0-3.0; m is about 0-3.0 and n is about0-1.0. In some embodiments, x is about 1.0; y is about 1.5 to 2; z is≦1; m is <1 and n is <1. There may also be elemental compositions thatinclude more than one type of heteroatom, halogen or metal.

In an exemplary embodiment, a hydrocarbon matrix may have a meltingpoint above about 40° C., for example, a hydrocarbon matrix may have amelting point between about 35° C. and 120° C., or between about 40° C.and about 100° C., or between about 40° C. and about 80° C.

Alternatively, the matrix may include a polymer such as a thermoplastic,e.g. polyethylene or polyethylene oligomers, polypropylene,polypropylene oligomers, polyolefins, and/or polyolefin oligomers. Acontemplated reinforcing layer comprises a matrix that may include athermoplastic polymer, with a molecular weight, or average molecularweight, above e.g. 10,000 g/mol, or above about 20,000 g/mol. Such solidmatrix may formed for example by providing a substantially liquid matrixcomposition that includes such a polymer, a wax, and/or a grease,wherein the liquid matrix forms a solid after a period of time, e.g. bydrying, curing and/or crosslinking. The substantially liquid matrix, incertain embodiments, has a viscosity less than about 1000 cPs, e.g. aviscosity between about 100 and about 1000, between about 150 and about800 cPs at 25° C. A low viscosity may allow the substantially liquidmatrix composition to flow between small diameter fibers of thereinforcing layer, and/or may facilitate filament winding.

Such a substantially liquid matrix may be in the form of an emulsion, asuspension, a colloid, an immiscible fluid blend, an ionic liquid,and/or a two phase system. A substantially liquid matrix can comprise asolution of hydrocarbons in an appropriate solvent. In some embodiments,a substantially liquid matrix may be an emulsion, e.g. an oil-in-wateremulsion or an water-in oil emulsion. An emulsion may have both thedispersed and continuous phase substantially liquid. In an embodiment,the emulsion comprises polymer particles, e.g. particles with an averagediameter of about 10 nm to about 100 μm, or about 100 nm to about 1 μm.A contemplated emulsion may include an emulsifier, tackifier, binder,and/or a surfactant.

For example, a substantially liquid composition for use in forming asolid matrix may be a latex matrix or dispersion, e.g. a water-baseddispersion of sub-micron polymer particles. When the water evaporates,the polymer particles may coalesce to form a solid, e.g. a solid film.Alternatively, a substantially liquid composition may include an anionicor cationic additive or composition which upon evaporation, drying,curing, or gelling are capable of form a solid matrix. For example, suchcomposition may comprise amine or ammonium moieties. In someembodiments, a substantially liquid composition may include inorganicsolids.

A reinforcing material or layer may include fibers. Such a layer mayinclude fibers in one or more plies, or the fibers may be randomlyoriented, or the material may include fibers in both configurations.

In one embodiment, the reinforcing layer can include two plies, whichcan optionally be counter-wound unidirectional plies. Such plies can bewound or formed around a inner object, for example, an inner pipe layer.The reinforcing layer(s) can include two plies, which can optionally bewound in about equal but opposite helical directions. In otherembodiments, the reinforcing material can include three, four, five,six, seven or eight, or more plies of fibers, each ply independentlywound, for example, in a helical orientation relative to thelongitudinal axis. Plies may have a different helical orientation withrespect to another ply, or may have the same helical orientation. Thereinforcing layer may include plies and/or fibers that have a partiallyand/or a substantially axial orientation. The reinforcing layer mayinclude plies of fibers with another material disposed between each ply,such as for example, an abrasion resistant material disposed betweeneach ply, or optionally disposed between only certain plies. In someembodiments, an abrasion resistant layer is disposed between plies thathave a different helical orientation.

When the reinforcing material or layer is part of a device or objectwith a longitudinal axis, e.g. a spoolable pipe, such reinforcing layerscan include fibers having at least a partially helical orientationrelative to this axis. The fibers may have a helical orientation betweensubstantially about thirty degrees and substantially about seventydegrees relative to the longitudinal axis. For example, the fibers maybe counterwound with a helical orientation of about ±40°, ±45°, ±50°,±55°, and/or ±60°. The reinforcing layer may include fibers havingmultiple, different orientations about the longitudinal axis.

Exemplary fibers include but are not limited to graphite, glass, carbon,KEVLAR, aramid, fiberglass, boron, polyester fibers, polyamide, ceramic,inorganic or organic polymer fibers, mineral based fibers such as basaltfibers, metal fibers, and wire. For example, fibers can include glassfibers that comprise e-glass, e-cr glass, Advantex®, s-glass, d-glass,borosilicate glass, soda-lime glass or a corrosion resistant glass.

The fibers can include structural fibers and flexible yarn components.The structural fibers can be formed of carbon, aramid, thermoplastic,polyester, polyamide, carbon, KEVLAR, inorganic compounds such as basaltor boron, metal and/or glass. The flexible yarn components, or braidingfibers, can be formed of either polyamide, polyester, aramid,thermoplastic, carbon, KEVLAR, boron, inorganic compounds such as basaltor boron, glass and/or ceramic. The fibers included in a reinforcingmaterial can be woven, braided, knitted, stitched, circumferentially,axially or hoop wound, helically wound, and/or other textile form toprovide an orientation as provided herein (e.g., in an embodiment, withan orientation between substantially about thirty degrees andsubstantially about seventy degrees relative to a longitudinal axis ofan object). The fibers can be biaxially or triaxially braided.

The reinforcing layer or material contemplated herein may include fibersthat are at least partially coated by a disclosed matrix, and mayinclude fibers that are embedded within a matrix, or may include fiberswith a matrix between at least some of the fibers, or may include acombination. The reinforcing material may comprise up to about 30% ofmatrix by volume, up to about 50% of matrix by volume, up to about 70%of matrix by volume, or even up to about 80% or higher by volume.

The reinforcing material contemplated herein may comprise more thanabout 5%, more than about 10%, more than about 20% or even more thanabout 30% by weight of solid hydrocarbon matrix.

As contemplated herein, the disclosed reinforcing material may alsoinclude polymers such as thermoplastics, for example polyolefins. Forexample, a reinforcing material may also include polyethylene such aslow density polyethylene, medium density polyethylene, linear lowdensity polyethylene, high density polyethylene, ultra-high molecularweight polyethylene, polypropylene, cross-linked polyethylene,polybutylene, polybutadiene, or polyvinylchloride. The reinforcingmaterial may further include pigments, plasticizers, flame retardants,UV stabilizers, thermal stabilizers, oxidative stabilizers, waterresistant materials, water absorbing materials, hydrocarbon resistantmaterials, hydrocarbon absorbent materials, permeation resistantmaterials, permeation facilitating materials, lubricants, fillers,compatibilizing agents, coupling agents such as silane coupling agents,surface modifiers, conductive materials, thermal insulators or otheradditives, or a combination of these.

Also contemplated herein are one or more methods for fabricating ormaking a reinforcing material or layer. Such a reinforcing material orlayer may be fabricated by applying a composition comprising hydrocarbonthat is substantially in liquid form, for example, a disclosedhydrocarbon at a temperature greater than about 40° C., or asubstantially liquid composition such as an emulsion which may be e.g.at about room temperature to fibers, for example, to a ribbon or bundleof fibers, to form a material. If a hydrocarbon is applied at atemperature greater than 40° C., the reinforcing layer or material canthen be cooled to room temperature, forming a matrix. If a substantiallyliquid composition is applied at, e.g. room temperature, the compositioncan be e.g. dried to form a solid matrix. The hydrocarbon and/orsubstantially liquid composition may be applied in line with fibermanufacture or in a secondary process, or it may be applied during thefiber winding operation of the tubing manufacture. Disclosed matrixcomponents such as hydrocarbons can also be applying in liquid form byfor example, forming an emulsion of hydrocarbons in water and thenapplying the composition to fibers. Such application may be followed byevaporation, drying, gelling, curing, or polymerization of the liquid.The matrix may be applied in-line with fiber manufacture, e.g. as partof the fiber sizing or as a coating, and/or applied in a secondary fibercoating operation to form a coated tow, strand, ribbon, rope, yarn orthe like. It may also be applied in-line with a filament windingoperation.

FIG. 1 illustrates a spoolable tube 10 constructed of an internalpressure barrier 12 and a reinforcing layer 14. The spoolable tube canbe generally formed along a longitudinal axis 17. Although illustratedin FIG. 1 as having a circular cross-section, the disclosed spoolabletube can have a variety of tubular cross-sectional shapes, including butnot limited to circular, oval, rectangular, square, polygonal, and/orothers.

The internal pressure barrier 12, otherwise referred to as a liner or afluid barrier, can serve as a pressure containment member to resistleakage of internal fluids from within the spoolable tube 10. In someembodiments, the internal pressure barrier 12 can include a polymer, athermoset plastic, a thermoplastic, an elastomer, a rubber, aco-polymer, and/or a composite. The composite can include a filledpolymer and a nano-composite, a polymer/metallic composite, and/or ametal (e.g., steel, copper, and/or stainless steel). Accordingly, aninternal pressure barrier 12 can include one or more of a polyethylene,a cross-linked polyethylene, a polybutylene, a polyvinylidene fluoride,a polyamide, polyethylene terphthalate, polyphenylene sulfide and/or apolypropylene, or combinations of these materials, either as distinctlayers or as blends, alloys, copolymers, block copolymers or the like.The internal pressure barrier may also contain solid state additives. Inone embodiment, the internal pressure barrier 12 includes a modulus ofelasticity greater than about approximately 50,000 psi, and/or astrength greater than about approximately 1,000 psi. In someembodiments, the internal pressure barrier 12 can carry at least fifteenpercent of the axial load along the longitudinal axis, at leasttwenty-five percent of the axial load along the longitudinal axis, or atleast thirty percent of the axial load along the longitudinal axis at atermination, while in some embodiments, the internal pressure barrier 12can carry at least fifty percent of the axial load along thelongitudinal axis at a termination. Axial load may be determined at theends of a tube. For example, at the ends, or a termination, of a tube,there may be a tensile (e.g. axial) load equal to the internal pressuremultiplied by the cross-sectional area of the inner diameter of thepipe.

Referring back to FIG. 1, the spoolable tube 10 can also include one ormore reinforcing layers 14. In one embodiment, the reinforcing layerscan include fibers having at least a partially helical orientationrelative to the longitudinal axis of the spoolable tube. The fibers mayhave a helical orientation between substantially about thirty degreesand substantially about seventy degrees relative to the longitudinalaxis 17. For example, the fibers may be counterwound with a helicalorientation of about ±40°, ±45°, ±50°, ±55°, and/or ±60°. Thereinforcing layer may include fibers having multiple, differentorientations about the longitudinal axis. Accordingly, the fibers mayincrease the load carrying strength of the reinforcing layer(s) 14 andthus the overall load carrying strength of the spoolable tube 10. Inanother embodiment, the reinforcing layer may carry substantially noaxial load carrying strength along the longitudinal axis at atermination.

The reinforcing layer(s) 14 can be formed of a number of plies offibers, each ply including fibers. In one embodiment, the reinforcinglayer(s) 14 can include two plies, which can optionally be counterwoundunidirectional plies. The reinforcing layer(s) can include two plies,which can optionally be wound in about equal but opposite helicaldirections. The reinforcing layer(s) 14 can include three, four, five,six, seven, eight, or more plies of fibers, each ply independently woundin a helical orientation relative to the longitudinal axis. Plies mayhave a different helical orientation with respect to another ply, or mayhave the same helical orientation. The reinforcing layer(s) 14 mayinclude plies and/or fibers that have a partially and/or a substantiallyaxial orientation. The reinforcing layer may include plies of fiberswith a tape or coating, such as a tape or coating that includes aabrasion resistant material or polymer, disposed between each ply,underneath the plies, on the outside of the plies, or optionallydisposed between only certain plies. In some embodiments, an abrasionresistant layer is disposed between plies that have a different helicalorientation.

The fibers can include structural fibers and flexible yarn components.The structural fibers can be formed of graphite, glass, carbon, KEVLAR,aramid, fiberglass, boron, polyester fibers, polyamide, ceramic,inorganic or organic polymer fibers, mineral based fibers such as basaltfibers, metal fibers, and wire. The flexible yarn components, orbraiding fibers, graphite, glass, carbon, KEVLAR, aramid, fiberglass,boron, polyester fibers, polyamide, ceramic, inorganic or organicpolymer fibers, mineral based fibers such as basalt fibers, metalfibers, and wire. The fibers included in the reinforcing layer(s) 14 canbe woven, braided, knitted, stitched, circumferentially wound, helicallywound, axially oriented, and/or other textile form to provide anorientation as provided herein (e.g., in the exemplary embodiment, withan orientation between substantially about thirty degrees andsubstantially about seventy degrees relative to the longitudinal axis17). The fibers can be biaxially or triaxially braided.

In one embodiment, the reinforcing layer(s) 14 includes fibers having amodulus of elasticity of greater than about 5,000,000 psi, and/or astrength greater than about 100,000 psi. In some embodiments, anadhesive can be used to bond the reinforcing layer(s) 14 to internalpressure barrier 12. In other embodiments, one or more reinforcinglayers are substantially not bonded to one or more of other layers, suchas the inner liner, internal pressure barriers, or external layer(s).

FIG. 2 illustrates a cross-section of a circular spoolable tube 10having an inner pressure barrier liner 12 and a first reinforcing layer14A, a second reinforcing layer 14B, and a third reinforcing layer 14C.Each of the reinforcing layers 14A-C may be formed of fibers, and eachof the reinforcing layers 14A-C successively encompasses and surroundsthe underlying reinforcing layer and/or pressure barrier 12.

The fibers in each of the reinforcing layers 14A-C can be selected fromthe same or different material. For example, the first reinforcing layer14A can comprise helically oriented glass fibers; second reinforcinglayer 14B can comprise a ply having helically oriented glass fiber atthe same angle, but at an opposite orientation of the first reinforcinglayer 14A; and third reinforcing layer 14C can comprise plies of fibershaving a clockwise and counter-clockwise helically oriented glassfibers. Further, the different reinforcing layers 14A-C can includedifferent angles of helical orientation. For example, in one embodiment,the different layers can have angles of orientation betweensubstantially about thirty degrees and substantially about seventydegrees, relative to the axis 17. Alternatively, the different layerscan have angles of orientation between substantially about forty-sixdegrees and substantially about fifty-two degrees, relative to the axis17. In some embodiments, the different layers 14A-C can have more thanone fiber within a layer, such as carbon and glass, and/or carbon andaramid, and/or glass and aramid. Further, the different layers 14A-C mayeach comprise multiple plies, each independent ply having a different,or substantially the same, helical orientation with respect to otherplies within a layer.

The reinforcing layer(s) 14 can include, in one or more embodiments ofthis disclosure, a hydrocarbon such as disclosed above. In someembodiments, the reinforcing layer(s) comprise a reinforcing material orhydrocarbon matrix as disclosed herein. For example, a spoolable tube,with for example, a diameter of about 1 inch to about 6 inches, isdisclosed herein for use with pressurized or unpressurized fluids up toabout 375 psi and/or fluids with a temperature up to about 180° F. Inthis and other embodiments, a matrix with a high modulus and a thin wallmay be sensitive to impact damage and/or collapse or kinking duringspooling, and therefore a hydrocarbon matrix may have a low modulus foruse in such an embodiment. In this and other embodiments, a matrix witha high modulus and a thin wall may have low allowable spooling orbending strain, but a hydrocarbon matrix with a lower modulus may allowfor higher spooling or bending strains.

In some embodiments, the permeability of a solid hydrocarbon matrix orthe reinforcing layer 14 is higher than the permeability of the internalpressure barrier liner 12, for example the permeability of a solidhydrocarbon matrix may be at least twice, three times or even at leastfive times higher than that of the internal pressure barrier liner 12.As temperature increases above, for example, room temperature, thepermeability of a hydrocarbon matrix may increases with temperaturefaster than the permeability of a pressure barrier increases withtemperature.

FIG. 3 illustrates a cross-section of a circular spoolable tube 10having an inner pressure barrier liner 12 and a first reinforcing layer14. Reinforcing layer 14 comprises a first ply of fibers 114A, anabrasion resistant layer 120, and a second ply of fibers 114B. Each ofthe plies 114A, B may be formed of fibers, and each of ply 114A,abrasion resistant layer 120, and ply 114B successively encompasses andsurrounds any other underlying reinforcing layer, abrasion resistantlayer, ply(s) and/or pressure barrier 12.

The fibers in each of plies 114A, B can be selected from the same ordifferent material. For example, the ply 114A can comprise at leastpartially helically oriented glass fibers; second ply 114B can comprisea ply having at least partially helically oriented glass fiber at thesame angle, but at an opposite orientation of the first ply 114A.Further, the plies 114A, B can include different angles of helicalorientation. For example, in one embodiment, the different plies canhave angles of orientation between substantially about thirty degreesand substantially about seventy degrees, relative to the axis 17.Alternatively, the different plies can have angles of orientationbetween substantially about forty-six degrees and substantially aboutfifty-two degrees, relative to the axis 17. For example, one ply 114Amay comprise fibers with helical orientation of about ±40°, ±45°, ±50°,±55°, and/or ±60°, and a second ply 114B may comprise fibers with aboutan equal but opposite orientation. One or more plies, or one or morefibers within a ply may be substantially axially oriented. Further, theplies 114A, B can include about the same angle of helical orientation.In some embodiments, the different plies 114A, B can have more than onefiber within a ply, such as carbon and glass, and/or carbon and aramid,and/or glass and aramid.

FIG. 4 illustrates a spoolable tube 10 elongated along an axis 17 andhaving an internal pressure barrier 12, a reinforcing layer 14, and atleast one external layer 56 enclosing the reinforcing layer(s) 14. Theexternal layer(s) 56 may otherwise be understood to be an outerprotective layer. The external layer 56 can bond to a reinforcinglayer(s) 14, and in some embodiments, also bond to an internal pressurebarrier 12. In other embodiments, the external layer 56 is substantiallyunbonded to one or more of the reinforcing layer(s) 14, or substantiallyunbonded to one or more plies of the reinforcing layer(s) 14. Theexternal layer 56 may be partially bonded to one or more other layers ofthe tube.

The external layer(s) 56 can provide wear resistance, UV, and impactresistance or thermal insulation, or selectively increase or decreasethe permeability. For example, the external layer 56 can provideabrasion resistance and wear resistance by forming an outer surface tothe spoolable tube that has a low coefficient of friction therebyreducing the wear on the reinforcing layers from external abrasion.Further, the external layer 56 can provide a seamless layer, to, forexample, hold the inner layers 12, 14 of the coiled spoolable tube 10together. The external layer 56 can be formed of a filled or unfilledpolymeric layer. Alternatively, the external layer 56 can be formed of afiber, such as aramid or glass, with or without a matrix. Accordingly,the external layer 56 can be a polymer, thermoset, a thermoplastic, athermoplastic elastomer, a thermoplastic foam, an elastomer, a rubber, aco-polymer, and/or a composite, where the composite includes a filledpolymer and a nano-composite, a polymer/metallic composite, and/or ametal. In some embodiments, the external layer(s) 56 can include one ormore of polyethylene, a cross-linked polyethylene, a polybutylene, apolyvinylidene fluoride, a polyamide, polyethylene terphthalate,polyphenylene sulfide and/or a polypropylene. The external layer 56 caninclude a modulus of elasticity greater than about approximately 50,000psi, and/or a strength greater than about approximately 1,000 psi. In anembodiment, the external layer 56 can carry at least ten percent, twentypercent, twenty-five percent, thirty percent or even at least fiftypercent of an axial load in the longitudinal direction at a termination.A seamless external layer can comprise, for example, a perforatedthermoplastic.

In some embodiments, the external layer 56 can be formed by extruding,while the layer 56 can be formed using one or more materials applied atleast partially helically and/or at least partially axially along thelongitudinal axis 17. The material can include, for example, one or morepolymeric tapes. In an example embodiment, the external layer 56 caninclude and/or otherwise have a coefficient of friction less than acoefficient of friction of a reinforcing layer 14.

Particles can be added to the external layer 56 to increase the wearresistance of the external layer 56. The particles used can include oneor more of ceramics, minerals, metallics, polymerics, silicas, orfluorinated polymers. For example, adding TEFLON (MP 1300) particles andan aramid powder (PD-T polymer) to the external layer 56 can reducefriction and enhance wear resistance. Particles, for example, TiO₂ orcarbon black, may be added to increase UV resistance of the externallayer.

It can be understood that pressure from fluids transported by thespoolable tubes 10 disclosed herein may not be properly released fromthe reinforcing layer(s) 14, and/or from the inner pressure barrierliner and/or from within the external layer, without, for example, anexternal layer having a sufficient permeability to provide such pressurerelease. Such accumulation of pressure can cause deterioration of thespoolable pipe 10, for example, external layer rupture or inner pressurebarrier collapse when bore pressure is reduced. Accordingly, in someembodiments, to allow for pressure release along the length of thespoolable pipe 10, the external layer(s) 56 can include and/or have apermeability at least five, or at least ten times greater than thepermeability of the internal pressure barrier 12, the reinforcing layer14, or a solid hydrocarbon matrix as disclosed herein. In someembodiments, a solid hydrocarbon matrix is selected so that thepermeability of the matrix is lower that the permeability of theexternal layer. For example, external layer(s) 56 include perforationsor holes spaced along the length of tube. Such perforations can, forexample, be spaced apart about every 10 ft, about every 20 ft, aboutevery 30 ft, and even about or greater than about every 40 ft. In oneembodiment, the external layer 56 can be perforated to achieve a desiredpermeability, while additionally and optionally, an external layer 56can include one or more polymeric tapes, and/or may be discontinuous.

The disclosed spoolable tubes 10 can also include one or more couplingsor fittings. For example, such couplings may engage with, be attachedto, or in contact with one or more of the internal and external layersof a tube, and may act as a mechanical load transfer device. Couplingsmay engage one or both of the inner liner, the external wear layer orthe reinforcing layer. Couplings or fittings may be comprised, forexample, of metal or a polymer, or both with or without elastomericseals such as O-rings. In some embodiments, such couplings may allowtubes to be coupled with other metal components. In addition, oralternatively, such couplings or fittings may provide a pressure seal orventing mechanism within or external to the tube. One or more couplingsmay each independently be in fluid communication with the inner layerand/or in fluid communication with one or more reinforcing layers and/orplies of fibers or abrasion resistant layers, and/or in fluidcommunication with an external layer. Such couplings may provideventing, to the atmosphere, of any gasses or fluids that may be presentin any of the layers between the external layer and the inner layer,inclusive.

With reference to FIG. 5, the disclosed spoolable tubes 10 can alsoinclude one or more energy conductors 62 that can be integral with thewall of the spoolable pipe. Accordingly, the energy conductors 62 can beintegral with the internal pressure barrier, reinforcing layer(s),and/or exist between such internal pressure barrier 12 and reinforcinglayer 14, and/or exist between the internal pressure barrier 12 and anexternal layer. In some embodiments, the energy conductor 62 can extendalong the length of the spoolable tube 10. The energy conductors 62 caninclude an electrical guiding medium (e.g., electrical wiring), anoptical and/or light guiding medium (e.g., fiber optic cable), ahydraulic power medium (e.g., a high pressure tube or a hydraulic hose),a data conductor, and/or a pneumatic medium (e.g., high pressure tubingor hose).

The disclosed energy conductors 62 can be oriented in at least apartially helical direction relative to a longitudinal 17 axis of thespoolable tube 10, and/or in an axial direction relative to thelongitudinal axis 17 of the spoolable tube 10.

FIG. 5 illustrates a spoolable tube 10 elongated along an axis 17wherein the spoolable tube includes an internal pressure barrier 12, areinforcing layer 14, and an energy conductor 62. In the FIG. 5embodiment, the energy conductor 62 forms part of the reinforcing layer14; however, as provided previously herein, it can be understood thatthe energy conductor(s) 62 can be integrated with and/or located betweeninternal pressure barrier 12 and the reinforcing layer 14.

A hydraulic control line embodiment of the energy conductor 62 can beeither formed of a metal, composite, and/or a polymeric material.

In one embodiment, several energy conductors 62 can power a machineoperably coupled to the coiled spoolable tube 10. For instance, aspoolable tube 10 can include three electrical energy conductors thatprovide a primary line 62, a secondary line 62, and a tertiary line 62for electrically powering a machine using a three-phase power system. Asprovided previously herein, the spoolable tube 10 can also includeinternal pressure barriers 12 for transmitting fluids along the lengthof the tube 10.

A method is also provided for fabricating or making a spoolable pipesuch as described above. Such a spoolable pipe may be fabricated, forexample, by applying a matrix comprising hydrocarbon that issubstantially in liquid form, for example, a disclosed hydrocarbon at atemperature greater than about 40° C., e.g. about 40° C. to about 80°C., to fibers, for example, to a bundle of fibers, to form a reinforcinglayer, and cooling the reinforcing layer to room temperature.

In an alternate embodiment, a method for producing a spoolable tube isprovided that includes providing an inner layer of said spoolable tube;applying a substantially liquid matrix composition comprising at leastone of: polyethylene, polyethylene oligomers, polypropylene,polypropylene oligomers, polyolefins, polyolefin oligomers, a wax,and/or a grease to fibers at a temperature between about 20° C. andabout 40° C., e.g at room temperature, drying said fibers so that asolid matrix composition between the fibers is formed; and winding thefibers around said inner layer. The liquid matrix composition may bedried at e.g. room temperature, or higher. In some embodiments, thesubstantially liquid matrix composition is an emulsion. In someembodiments, the method includes forming a tow comprising said fibers.The liquid matrix composition may be applied during, before, and/orafter the fiber or tow winding.

The liquid matrix and/or the substantially liquid matrix composition maybe applied during or after fiber manufacturing, for example, at the sametime that a sizing may be applied to the fibers. The fiber-matrix tow orthe coated fibers may then be applied or wound on an inner layer of aspoolable tube. A substantially liquid matrix composition or a liquidmatrix may be applied to the fibers by for example dipping, brushing,soaking, or other applications as known to those skilled in the art.

For example, a method of producing a fiber tow is provided that includesforming fibers such as glass fibers; applying a liquid hydrocarbon tothe fibers and/or dipping the fibers into a liquid hydrocarbon or asubstantially liquid and drying and/or cooling the fibers. Such a methodmay include pulling fibers that have been, for example, dipped in orcoated with a liquid hydrocarbon or disclosed liquid composition into atow before cooling. Such a tow can be wound onto a tube beforeapplication to an inner layer of a spoolable tube, or can be applied orwound directly onto such a layer. Alternatively, the hydrocarbon and/orthe substantially liquid matrix composition may be applied before,during or after the fibers are wound onto a pipe layer.

Applying a liquid hydrocarbon matrix at a temperature above roomtemperature, and cooling the matrix so that it solidifies at roomtemperature, or applying a liquid matrix composition at e.g. roomtemperature may also provide the advantage of at least partiallyeliminating the need to cure a matrix during pipe manufacture. Suchcuring step, usually at elevated temperature, often limits productionspeeds.

EXEMPLIFICATION Example 1

Properties of various tows, or bundles of glass fibers embedded invarious low molecular weight hydrocarbon matrices, are indicated in FIG.6. LOI refers to loss on ignition, or the weight fraction of the lowmolecular weight hydrocarbon. FIVE refers to fiber volume fraction foreach tow; MVF refers to the matrix volume fraction.

Unless otherwise stated, use of the word “substantially” can beconstrued to include a precise relationship, condition, arrangement,orientation, and/or other characteristic, and deviations thereof asunderstood by one of ordinary skill in the art, to the extent that suchdeviations do not materially affect the disclosed methods and systems.

Elements, components, modules, and/or parts thereof that are describedand/or otherwise portrayed through the figures to communicate with, beassociated with, and/or be based on, something else, can be understoodto so communicate, be associated with, and or be based on in a directand/or indirect manner, unless otherwise stipulated herein.

Although the methods and systems have been described relative to aspecific embodiment thereof, they are not so limited. Obviously manymodifications and variations may become apparent in light of the aboveteachings. Many additional changes in the details, materials, andarrangement of parts, herein described and illustrated, can be made bythose skilled in the art. Accordingly, it will be understood that thefollowing claims are not to be limited to the embodiments disclosedherein, can include practices otherwise than specifically described, andare to be interpreted as broadly as allowed under the law.

All publications and patents mentioned herein, including those itemslisted below, are hereby incorporated by reference in their entirety asif each individual publication or patent was specifically andindividually indicated to be incorporated by reference. In case ofconflict, the present application, including any definitions herein,will control.

The composite tubes disclosed in U.S. Pat. Nos. 5,921,285; 6,016,845;6,148,866; 6,286,558; 6,357,485; and 6,604,550.

1. A spoolable pipe, comprising: an internal pressure barrier formedabout a longitudinal axis; at least one reinforcing layer enclosing theinternal pressure barrier and comprising fibers and a solid hydrocarbonmatrix, wherein said solid hydrocarbon matrix is solid at about 25° C.and said matrix comprises hydrocarbons having an average molecularweight of less than about 20,000 grams/mole; and an external layerenclosing the at least one reinforcing layer. 2.-19. (canceled)
 20. Aspoolable pipe, comprising: an internal pressure barrier formed about alongitudinal axis; at least one reinforcing layer enclosing the internalpressure barrier and comprising fibers and a solid matrix wherein saidsolid matrix has a tensile modulus between about 10 and 90,000 psi, andwherein said reinforcing layer is formed at least by applying to saidfibers a substantially liquid matrix composition having a viscositybetween about 10 and about 10,000 cPs at 25° C.
 21. The spoolable pipeof claim 20, wherein the at least one reinforcing layer comprises atleast two plies of fibers.
 22. The spoolable pipe of claim 21, whereinthe two plies of fibers have at least a partial helical orientationrelative to the longitudinal axis.
 23. The spoolable pipe of claim 20,wherein said substantially liquid matrix composition is capable offlowing between said fibers.
 24. The spoolable pipe of claim 20, whereinsaid substantially liquid matrix composition has a viscosity betweenabout 100 and about 5000 cPs.
 25. The spoolable pipe of claim 20,wherein said substantially liquid matrix composition is an emulsion, asuspension, a colloid, a immiscible fluid blend, or two-phase system.26. (canceled)
 27. The spoolable pipe of claim 26, wherein saidsubstantially liquid matrix composition comprises at least one of: anemulsifier, tackifier, binder and a surfactant.
 28. The spoolable pipeof claim 26, wherein said substantially liquid matrix compositioncomprises at least one of: polyethylene, polyethylene oligomers,polypropylene, polypropylene oligomers, polyolefins, polyolefinoligomers, paraffin waxes, or a grease.
 29. The spoolable pipe of claim20, wherein said substantially liquid matrix composition comprisespolymer particles.
 30. The spoolable pipe of claim 29, wherein saidpolymer particles have an average diameter between about 10 nm and about10 μm.
 31. The spoolable pipe of claim 20, wherein said substantiallyliquid matrix composition comprises anionic or cationic moities that arecapable of forming a solid upon evaporation, drying, curing or gelling.32. The spoolable pipe of claim 31, wherein said substantially liquidmatrix composition comprises a compound comprising an amine or anammonium moiety.
 33. The spoolable pipe of claim 20, wherein saidsubstantially liquid matrix composition comprises inorganic solids. 34.The spoolable pipe of claim 20, wherein said substantially liquid matrixcomposition comprises a water-based dispersion.
 35. The spoolable pipeof claim 20, wherein said internal pressure barrier comprises at leastone of: a metal, polyethylene, cross-linked polyethylene, polyvinylidenefluoride, polybutylene, polyamide, polypropylene, polyethyleneterphthalate, or polyphenylene sulfide.
 36. (canceled)
 37. The spoolablepipe of claim 35, wherein the permeability of said reinforcing layer ishigher than the permeability of said internal pressure barrier.
 38. Thespoolable pipe of claim 20, further comprising an external layer. 39.The spoolable pipe of claim 38, wherein said external layer wherein thepermeability of said external layer is higher than the permeability ofsaid solid matrix.
 40. The spoolable pipe of claim 38, wherein saidexternal layer comprises at least one of: polyethylene, cross-linkedpolyethylene, polybutylene, polyvinylidene fluoride, polyamide,polypropylene, polyethylene terphthalate, or polyphenylene sulfide. 41.The spoolable pipe of claim 38, wherein said external layer comprises afoam.
 42. The spoolable pipe of claim 41, wherein said foam comprises atleast one of: a thermoset polymer, a thermoplastic polymer, anelastomer, a rubber, closed cells and open cells.
 43. The spoolable pipeof claim 20, wherein said fibers comprise a glass, an aramid, a carbon,a ceramic, a metal, a mineral, or a polymer, or combinations thereof.44. The spoolable pipe of claim 20, further comprising an energyconductor.
 45. The spoolable pipe of claim 20, wherein said spoolablepipe further comprises at least one of: afire retardant, a UVstabilizer, an oxidative stabilizer, and a thermal stabilizer.
 46. Thespoolable pipe of claim 20, wherein said spoolable pipe furthercomprises a pigment.
 47. The spoolable pipe of claim 20, wherein saidsolid matrix is formed by further drying, curing and/or crosslinkingsaid substantially liquid matrix composition.
 48. A method for producinga spoolable tube comprising: providing an inner layer of said spoolabletube; applying a substantially liquid matrix composition comprising atleast one of: polyethylene, polyethylene oligomers, polypropylene,polypropylene oligomers, polyolefins, polyolefin oligomers, a wax,and/or a grease to fibers at a temperature between about 20° C. andabout 40° C.; drying said fibers so that a solid matrix compositionbetween the fibers is formed; and winding said fibers around said innerlayer. 49.-54. (canceled)